Telephone system.



F. G. AGRELL. TELEPHONE SYSTEM. ArPLIuA'rIoH rILrm 00T. 1o, 190e.

LLL Patented May13, 1913.

Hmm

c ally operated FRANS GUN'NAR .AGR-ELL, OF STOCKHOLM, SWEDEN.

TELEPHONE SYSTEM.

that .car

Specification of Letters Patent.

Patented May 13, 1913.

Application tiled October 10, 1906. Serial No. 338,310.

lle it known that l, Finns GUNNAR AG- ema., a subject et the. King of Sweden, and reaident ol Stockholm, Sweden, have invented-certain new and useful Improvements in Telepl'umc Systems, ot which the following is a specitieation.

his invtnitien relates to telephone systems and has for its object the provision et a new system of devices and connections..

adapted tor use in a telephone exchange and by iin-.ans change is greatly simplified and rendered partially ziutomatic.

tine object opt my invention is to do away with that part. ott the operation of the exchange which consists in connecting the calling subscribers local line with a switching circuit.. this being accomplished automaftcalty by the use ot' my invention.

."inother object and result accomplished by the use o't my invention is the distributien et the, (iper-.defs load which lieretoforc has been accomplished by means of manudistributing switchboards.

ABy 'the Vuse otmsuitable devices, which will he more fully tflescribed hereinafter, a calling subscriber is in my system automatically connected to a switching circuit controlled by an operator or other means which is not busy at the time.

Other objects will bein part obvious and in part pointed out hereinafter.

'ify means oit a devicewhich I have designated as a connector and which may be locatec'l in the excluu'ige, any slll' sci'ibe1"s calling will. be automatically connected to a switching circuit controlled by a not busy i operator or other means.

in the drawings accompanying this specicaticn t have illustrated one :form or emhraliment of my ,invention in a central energy or commen battery system with' a combination of circuits and devices. many ot' which may be altered to meet the various remiiremeuts of telephone service and to adapt the same tor use with other systems.

'lhe figure represents diagrammatically the circuits ol a Tentral exchange 'forming art et a system such as above described.

"f'he, connector is int'ticated diagrammatieatly in the accompanying drawings by the movable arms t and l and the motorl Btl-31, and it is not thought.v necessary to describe the same in detail here further than to state that the movable arm et carries ter- Vof which the operation of the ex.

minals 1 to which is connected the line from the subscribcrs station, there being as many arms and sets of' terminals as subscribers. The movable arms carry terminals Q to which are connected the switching circuits from'the plugs and jacks, or selecting devices, and these terminals are so positioned that connection may be made with any sub- Scribers terminals. "Ihe magnet opcrates the latch 11 to release the arm -t allowing the same to fall and cause the terminals l to engage the terminals 53 on the arm 15. The magnet 18 then operates to swing the arm 15 into such position that it will not be engaged by a subsequently op erated subscriber-s line and is held in suchV a position by the latch 2() which is operated by the magnet 21 to release the same, when the arm 15 will assume its former osition. It will be understood that the movable arms 4v and 15 may be mounted upon the armature shaft ot`. the motor 30-31, or otherwise suitably connected therewith, so that when the motor is connected in circuit the arms are restored to their original positions, breaking the contact between the terminals 1 and 2, but. when disconnected are tree to fall by gravity to make the desired connections. The motor 30-31 is shown in dotted outline in its position relative to the movable arms 4 and their shaft 3. The construction of this portion of the device is shown in detail in Figures 3, 4 and 5 of my tao-pending application filed contemporaneoust with this application junder Serial No. 388,309. An important feature of the this connector is that all cona large group of subscribone hundred and the system using nections between ers lines for instance, switching circuits assigned to said group are performed by the same device. In systems formerly devised a plurality of devices in the strict meaning of the word, each individual to a subscribers line or individual to a switching circuit have been employed making such a system extremely complicated.

Referring now to the drawing, (34 represents a subscriber-s station connected to a common battery type of exchange by means of the line :1Q-53. In the central exchange, said lines carry multiple jacks 54, one at cach multiple board as now regularly used. Instead ot' the regular answering jack the terminals 1 o'l the connector are used. Current is supplied to the subscribers station -lead 59, the releasing magnet 60, the contact 61 on 'the relay 58 to the other side 53 of the subscribers line. The usual answering cord and plug are substituted by the terminals 2 of the connector. Only a few cords from each operator goes to each connector, the remaining being connected to other similar connectors. If the subscriber takes his receiver 62, ottn the hook 63 current will iow from the battery through the resistance 55, over the-contact 57, over the line 52, through the transmitter 64 and induction coil4 65 back to the line 53 and from there through the contact 61 to the releasing magnet 60, line 59 back to ground and battery. Now the releasing magnet 60 Will operate its latch 11 releasing the arm t of the connector.

This arm will now fall until the terminals 1 engage and make Contact with the terminal bars 2.on th'e .arm 1,5. contactnis made between terminals 66 -and 67 andthe' ground side of battery 56 is com;

neeteditbreush the lii, 68 t0 the magnet 18, fbelaf thelamp. .10. the plus. Contact.' 7 1 andnleads 72 Handg 97 to, battery. Thus a comp'lete `cireuitris formedl and the magnet 1 6 ,",tvill operate, carrying the arml 15 to its busy posi'tionwhere itis locked by the latch 20. yAt the same time the lamp lights, indicating that a subscriber has called. Then the arm 4t moved away from its origi-l nal position contact was made between springs shown at 22 and current ivent from battery, over the resistance the lead 78, the. contact 22 to the third conductor 74.- in the multiple, making the multiple jacks of -saidvsubscriber indicate busy The current also Went from the contact 22 through the'line 75 and the relay 5S to ground. Now this relay operates and the contacts 57 and 61 are broken, disconnecting the battery from the subscribers line. This line is now connected to battery through lead 76, retardation coil 77 line 7S, through contacts 1 and 2 of the connector to the subscribers line and then through lead 7 9 and relay 80 to ground. Through the contacts 1 and -2, therleads 78 and 79 and the condensers 81 and 82 the subscriber is connected to the cord circuit 8f3-841 ending in the plug 85. This cord circuit is provided With the ordinaryyineans for listening in on the operators side and for ringing, not shown in the drawing. .i When the lamp 70 lighted the operatorthrew the key 86 to connect her talking/circuit to the cord, asked the subscriber for thexnumber Wanted and lifted up the plugiA and connected it to the desired multiple jack. I When the key 86 was thrown current Went from the battery through the lines 76 and 87 to the key contact 88 and out At the Sametime on a line 89, which branches to every connector to Which trunks go from said operators position. This branch line 90 goes to a relay 91 and from there to ground. Now this relay operates and connects the electromagnet 18 to the battery on one side-by means of the contact 92 and to the other side of battery through ground by means ot the contact 93. All trunks belonging to said operator will now be moved out of reach for any subscribers line by the operation of the connector arm as above described as long as the operator is busy that is, as long as the key 86 is thrown. They are notlocked in this position, however, as the. releasing magnet 21 is also connected to the battery through the contacts 94.- and 95 so that When key 86is restored and the contact 88 broken the arm 15 will go back to its original position. Vhen theoperator lifted up the plug 85 the contact 71 Was broken, thus putting out the lamp 70 and-also breaking the current in the magnet 18.. Now consider station 64 as the vsubscriber being called, the ydiagram of connections being the same asnfor the calling subscriber.

lVhen the operator plugs in totherdesired' inultipleijaclr 51 `current lwill go oierrthe line 97vthe resistance 98, thesleeye'lf to the. third conductor 74e of said subscribers multiple and through his ciitoi1t".i'elay 5Si toground. The cut-out relay will operate, breaking yaway that, currentfrom its line which Went over the resistance 55 and the' release magnet 60. This subscriber is'now, indicated busy and his calling arin '4 cannot be released. He is nowl connectedl through to the calling subscriber and ceives current from the con'unon battery through the lead T6. the retardation coil 100 to they one side ot the line and is connected with the other side through the relay 101 to the ground side ot the battery. Now current goes from the leads 97 and 72 to the plug contact 102. which was Aclosed by the lifting ofthe plug.. the relay 103. the lamp 104, the'` lead 105 and contactl 106 of the relay 101 back to lground and battery. Now the lamp 104 lights. now signals to the subscriber in. the ordinary manner. lVhe'n the called subscriber takes his receiver 62 off the hoolr'63 the relay 101 is energized and the contact 106 is broken, thus-'putting out the lamp 104'. Now the two subscribers are connected and vin conversation. Then the. call is finished and both subscribers put their receivers on the hooks the current in relays 60 and 101. is broken and contacts 109 and 106 go 'back to their original positions. Current nonv goes through the lead 97, lead '72.rthe plug Contact 102, the relay 103, to the lamps 104.F` and 107. From the lamp 107 the current goes through the lead 108 to the Contact 100 ot the relay/ to ground, and from the lamp 1 The operator 111)1 it goes through the lead 105 and contact 106 to ground. Both lamps now light and the relay 103 is operated. lurrent goes now to the contact 110 thelead 111, the release magnet 21, the lead 112, the contact 113 of relay 101, the contact 114 of relay 80 the lead 1 15 to the restoring motor S30-31, back to ground and battery. Now thc arm 1 5 is released and goes back to its original position and the motor car ries the arm 4 back to its original position. The contact is broken and the cut` ofi' relay 58 goes back to` its original position. Everything is now restored as far as the calling subscriber is concerned and the operator pulls out the plug S5 from the jack 51 of the called subscriber', thus breaking the current from his cut otf relay 58. Now this subscribers apparatus is restored. When the pluggoes down to its seat the contact 102 is broken thus disconnecting the relay 103 and the lamps 1011 and 107.

VWhen the relay 103 ceases to operate the current is broken from the release magnet 21 and the restoring motor 30 and everything is now restored to its original position.

From the description ot' my system as above illustrated it will be seen that when an operator or selective means is busy attending to a call all ot` the switching circuits controlled by said operator or selective means are automatically indicated busy and rendered inaccessible to any subsequent call and any such subsequently calling subscriber will be auton'latically connected with a switching circuit controlled by a not busy operator. It will also be seen that in my System the connection ot' the calling subscriber to a switching circuitl is made almost instantaneously. Consequently a more eilicient service than is possible with present systems can be given where my system is em loyed and this can be accomplished w1 l1 a smaller number of operators or selective devices.

It will be understood that the term in'dicated busy. and similar terms,.are herein used in their broadest sense. 1t will be cvi dent that there are many ways in which a circuit may be indicated busy and the means here shown and described not only till this function but also operate to render the busy circuits inaccessible for use while the operator or selecting device which controls such circuit or group 'of circuits is busy or being operated.

`As many changes could be made in the `above constructiomand man v apparently widely different embodiments ot my invention designed without defun-ting from the scope thereof, I `intend that all matter contained in the above description or shown in the accompanying drawingsl slall be interpreted as illustrative merely ot' an operativc embodiment of my invention and not in a limiting sense.

What l claim is:

1. In a telephone exchange, in combination, a number of switchingr devices adapted to be controlled by a number of operators, a number of movable terminals, a number of circuits connectingr said switching devices and said movable terminals, a number of subscribers lines each provided with movable terminals, means adapted to move the jgrminals of one of said subscribers ylines into operative engagement with the terminals of one of said switching circuits, means adapted to move said last named terminals when so connected to such a position that the same will not be engaged by a subsequently operated sub scribers terminals, means for movlng the terminals of all other switching circuits controlled by any one operator into such a position that the same will not be engaged by` a subsequently operated subscribers terminals when said operator is busy, and means for restoring the terminals to their original position.

2'. In a telephone exchange, in combination, a number of switching devices adapted to be controlled by a number of operators7 a number of movable terminals, a number of circuits connecting said switching devices and saidanovahle terminals, a nurnbcr, of subscribers lines, a device adapted .toiconnect one of said subscribers lines with the terminals of one of said switching circuits, means adapted to automatically move said terminals when so connected to such a position that the san1e will not be engaged by a subsequent-ly operated subscribers line, means for moving the terminals of all other switching circuits con trolled by any one operator into such a position that the same cannot loe connected with a subsequently operated subscribers line when said operator is busy, and means for restoring the terminals to their original position.

3. In a telephone exchange, in combination, a number of switching devicesadapted to be controlled by a number of operators, a number ol movable terminals, a number of circuits connecting said switching devices and said movable terminals, a number of subscribers lines each provided with movable terminals, electrically operated means adapted to move the terminals ot' one of said subscribers lines in to operative cngagement with thc terminals of one of said switching circuits, electrically operated means adapted to move said last named terminals when so connected to such a position that the same will not be engaged by a subsequently operated subscribers terminals, electrically operated means tor moving the terminals of all switching circuits controlled by any one'operator intosuch a p0- sition that the same Will' notbe engaged by a subsequently operated subscribers terminals, When said operator is busy, and means for restoring the tenninals to their original position.` l

4. In a telephone'exchange, in combina- `ti0n, a niunber of switching devices, a num- 1, bero'f movable terminals,r a number of c11'- l0 cuitsconnecting said switching devices and said movable terminals, a numberof subelectrically operated means formoving the terminals of all switehingvcircuits into such a posit-ion that the same will not be engaged by a subsequently operated subscribers ten minals7 and means for restoring the terminals to their original position.

Signed at New York, in the county 0f New York and State of NeW`York this 9th day of Oct. A. D. 1906.

FRANS GUNNAR AGRELL.

Witnesses W. FoRsYTH, LEWIS J. DooLnTLE. 

